JPH0545934B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical recording material that is capable of multiplex recording with light of different wavelengths at the same location on the same material by utilizing the photochemical hole burning phenomenon. [Conventional technology] The photochemical hole burning (PHB) phenomenon is a method in which monochromatic light is irradiated onto a material that undergoes a photochemical reaction at an extremely low temperature similar to the temperature of liquid helium, and only guest molecules that absorb the light are selectively absorbed. It excites and causes photochemical changes.
This photochemical change can form sharp holes in the material's absorption spectrum, so optical recording in photon mode is possible depending on the presence or absence of holes. Furthermore, by sequentially recording while changing the wavelength of the irradiated light, wavelength multiplexing recording can be performed at the same location on the same material. Using this PHB phenomenon,
It has the potential to improve recording density by approximately 1000 times compared to conventional optical digital recording media such as compact discs and laser discs.

Optical recording materials that use this PHB phenomenon are
In order to increase the wavelength multiplicity during optical recording, which consists of a guest molecule that is a photoreactive compound and a host for dispersing it, it is necessary to It is better to use an amorphous material. For this purpose, conventionally, organic or inorganic polymers have been suitably used as the host, such as materials in which the guest is tetraphenylporphine and the host is polymethyl methacrylate (Optics, 14-(4) 263-269). or,
A material in which the guest is quinizarine and the host is silicate glass (J.Appl.phys., 58(9)3559-3565) is known.

[Problems to be solved by the present invention] However, conventional PHB materials have the disadvantage that they become unstable at temperatures higher than the liquid helium temperature, making writing, saving, and reading of records uncertain. . One reason for this is that irreversible structural changes are thermally induced in the PHB material, resulting in different microstructures around each guest molecule. Furthermore, the recording density was also insufficient.

The present invention aims to solve the drawbacks of the conventional technology, and by using an ionic porphine derivative in which the active proton is deuterated as a guest, the half width of the hole is small and high density recording is possible. It is an object of the present invention to provide a wavelength multiplexing recording medium that has high thermal stability.

[Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration.

"A composition comprising a guest component and a host component as main components, wherein (a) the guest component is a porphyne derivative having an ionic group represented by the following general formula [A], and (b) the host component is It is a polymer that does not have active protons that can be exchanged with the deuterium of the guest component mentioned above.

Porphyne-based PHB-based recording material characterized by the following.

(In the formula, D is deuterium, and at least one selected from X ₁ , X ₂ , X ₃ , and X ₄ is an aryl group having an ionic group or an ion having an alkyl group having 1 to 6 carbon atoms. is a sexual heterocyclic group, and the others are
It is a hydrogen atom or a nonionic group. ) In other words, compared to recording materials that use conventional porphin-based guests, in the case of materials consisting of ionic porphin derivatives in which active protons are deuterated and polymers that do not have active protons, It has good affinity between guest and host due to interaction, and is less susceptible to thermal disturbances because the active proton of the porphine ring is deuterated. Therefore, it is presumed that irreversible structural changes upon temperature rise will be reduced. As a result, an increase in the half width of a hole formed in the absorption spectrum of the material is suppressed, and the thermal stability of recording is improved.

In the present invention, at least one selected from X ₁ , X ₂ , X ₃ , and X ₄ is an aryl group having an ionic group or an ionic heterocyclic group having an alkyl group having 1 to 6 carbon atoms. , otherwise X ₁ ~
X ₄ is a hydrogen atom or a nonionic group.

The ionic group that the guest component has may be any of a cationic group, anionic group, and amphoteric ionic group.

As the cationic group, a quaternary amino group, an N-alkylpyridinium group, etc. are preferably used. This is because it maintains a stable ionized state in the host. Particularly preferably, general formula [B] (However, in the formula, R ₁ to _{R 12} are alkyl groups.) 5,10,15,20-tetra(4-N,
N,N-trialkylaminophenyl) deuterated product of porphine or general formula [C] (However, in the formula, R ₁₃ to _{R 16} are alkyl groups having 1 to 6 carbon atoms.) A deuterated product of 5,10,15,20-tetra(4-N-alkylpyridinium)porphine represented by is used. This is because in the porphine derivative of the general formula [B], the porphine ring and the quaternary amino group are separated by a phenyl group, and in the porphine derivative of the general formula [C], the charge of the pyridinium group is transferred to the conjugated system. This is because the cation moiety is less likely to affect the photochemical reactivity of the porphine ring since it is dispersed. R ₁ to _{R 12} of general formula [B] and of general formula [C]
More preferably, the alkyl group represented by R ₁₃ to _{R 16} is a methyl group. This is because the methyl group has the most compact structure, has a small degree of freedom of movement when dispersed in the host, and is presumed to be less likely to undergo irreversible structural changes at low temperatures.

These cationic porphine derivatives are present in the material together with appropriate anions. The anion should be selected from the viewpoint of compatibility with the host component, but p-toluenesulfonate ion, I ^- , Br ^- , Cl ^- , ClO ₄ ^- , CH ₃ , CO ₂ ^- ,
BF ₄ ^- etc. are preferably used.

The deuterated product of 5,10,15,20-tetra(4-N,N,N-trialkylaminophenyl)porphine is 5,10,15,20-tetra(4-N,N,N-trialkylaminophenyl)porphine synthesized from acetaminobenzaldehyde and pyrrole. 4-
It is obtained by hydrolyzing porphine (acetaminophenyl) with an acid, reacting it with a quaternizing agent such as alkyl iodide, and then reacting it with heavy water. Also,
The deuterated product of 5,10,15,20-tetra(4-N-alkylpyridinium)porphine is 5,
It is obtained by quaternizing 10,15,20-tetra(4-N-pyridyl)porphine with a quaternizing agent such as alkyl iodide and then reacting it with heavy water.

Examples of anionic groups include SO ₃ ^- group, CO ₂ ^- group, O ^-
and the like are preferably used. This is because it maintains a stable ionized state in the host. Also, general formula [D] (However, in the formula, R ₁₇ to R ₂₀ are anionic groups.) Porphine derivatives represented by the following are preferably used. This is because, in the porphine derivative of general formula [D], the porphine ring and the anionic group are separated by the phenyl group, so that the anion moiety is less likely to affect the photochemical reactivity of the porphine ring.

This porphine derivative having an anionic group is present in the material together with a suitable cation. The cation should be selected from the viewpoint of compatibility with the host component, and alkali metal ions, deuterium ions, alkaline earth metal ions, and ammonium ions are preferably used.

In addition, the porphine derivative having an anionic group represented by the general formula [D] can be prepared by reacting 5,10,15,20-tetraphenylporphin with a polybasic acid and then reacting it with heavy water, or It is obtained from a precursor synthesized from a benzaldehyde derivative having a group that can be an anionic group and pyrrole.

Examples of porphine derivatives having a zwitterionic group include deuterated derivatives of tetra[3-(N-sulfonatoalkyl-N-alkylamino)phenyl]porphine, tetra[3-(N-carbonatoalkyl-N- deuterium-substituted product of tetra[4-(N-sulfonatoalkyl)pyridinium]porphine, deuterium-substituted product of tetra[4-(N-carbonatoalkyl)pyridinium]porphine, deuterium-substituted product of tetra[4-(N-carbonatoalkyl)pyridinium]porphine) Substituted forms and the like are preferably used.

In addition, in _the present invention, among X ₁ , X ₂ , X ₃ , and It is an atom or a nonionic group, and the nonionic group includes, for example,
Examples include phenyl group, methoxyphenyl group, nitrophenyl group, naphthyl group, and methoxynaphthyl group.

The polymer used in the present invention may be any polymer that is compatible with the porphine derivative having an ionic group as a guest component and does not have active protons that can be exchanged with deuterium. Examples of polymers that are compatible with porphyne derivatives include polyethylene oxide, polyvinylpyridine, polyvinylpyrrolidone, polyhydroxyethyl methacrylate, polymethacrylic acid, polyacrylic acid, polymethacrylamide, polyacrylamide, cellulose acetate, and sodium polyvinylsulfonate. Water-soluble organic polymers and inorganic polymers such as silicate glass are preferably used, and polyvinyl alcohol or sodium polystyrene sulfonate is particularly preferred. Among these, in the case of a polymer having active protons that can be exchanged with deuterium as a guest component, such as polyvinyl alcohol, the active protons are deuterated and used. Since the porphine derivative having an ionic group, which is a guest component, is soluble in a polar solvent, it is compatible with these aqueous polymers and silicate glass synthesized by the sol-gel method, and is easily dispersed. In particular, polyvinyl alcohol has strong hydrogen bonding properties, so it is estimated that it is unlikely to undergo thermal structural changes at low temperatures.Also, sodium polystyrene sulfonate has a benzene ring in its side chain, so it does not interact with the guest polyfin derivative. It is most preferred as a host component because of its high affinity.

If the concentration of the guest component in the optical recording material of the present invention is too high, hole generation characteristics will deteriorate due to energy transfer between guest molecules, and if it is too low, the S/N during recording and reading will decrease. subject to restrictions. Therefore, the preferred guest concentration is 10 ^-1 based on the volume of the host polymer.
-10 ^-5 M, particularly preferably 10 ^-2 -10 ^-4 M.

Furthermore, additives such as stabilizers that do not have an absorption band that overlaps with the absorption band of the porphine derivative having an ionic group may be added to the recording material of the present invention;
The guest component and host component are the main components, and the total
It is preferable that the content is 95% or more. this is,
This is to prevent the interaction between host and guest from being impaired by the additive.

[Example] The present invention will be described in more detail based on Examples below, but the present invention is not limited thereto.

After heating and dissolving 0.2 g of 5,10,15,20-tetra(4-N-methylpyridinium)porphine tetraiodide (manufactured by Wako Pure Chemical Industries, Ltd.) in 4 g of heavy water,
After drying, a deuterated porphine in which active protons were deuterated was obtained. Separately, polyvinyl alcohol (degree of polymerization = 2000, degree of saponification = 100%) 1
g was heated and dissolved in 15 g of heavy water and then dried to obtain deuterated polyvinyl alcohol in which the active protons were deuterated. This deuterated porphin and deuterated polyvinyl alcohol were dissolved in heavy water and dried to obtain a film of deuterated porphin/deuterated polyvinyl alcohol with a guest concentration of 20 mM.

After cooling this film to liquid helium temperature,
Laser light with a wavelength of 640 nm and an intensity of 1 mW/cm ² was irradiated to form PHB holes with an absorption rate change of 40%. At this time, the half width of the hole was 0.25 cm ^-1 .

On the other hand, a film of non-deuterated 5,10,15,20-tetra(4-N-methylpyridium)porphine tetraiodide/polyvinyl alcohol also has PHB holes with an absorption rate change of 40%. When a hole is formed, the half width of the hole is
It was 1.10cm ^-1 .

The half-width of the hole was reduced by 1/4.4 times due to deuteration of the active proton. As a result,
The number of holes that can be formed in the same absorption band increased by a factor of 4.4, that is, the multiplicity increased by a factor of 4.4.

Example 2 4.6 mg of 5,10,15,20-tetra(4-N-methylpyridinium) porphine tetraiodide (manufactured by Wako Pure Chemical Industries, Ltd.) and 5 g of sodium polystyrene sulfonate were heated and dissolved in 50 ml of heavy water, and then dried. By drying under a nitrogen atmosphere, a film of deuterated porphine/sodium polystyrene sulfonate with a guest concentration of 1 mM was obtained.

This film has a wavelength of 645 nm and an intensity of 1 mW/cm ²
PHB holes were formed by irradiating with laser light. FIG. 1 illustrates the relationship between the temperature of the sample and the half-width of the generated holes. In this sample
I was able to form a hole even at 60K.

Example 3 Tetrasodium 5,10,15,20-tetra(4
- Sulfonatophenyl) porphine (manufactured by Wako Pure Chemical Industries, Ltd.) 4.8 mg and sodium polystyrene sulfonate 5 g were heated and dissolved in 50 ml of heavy water, and then dried under a dry nitrogen atmosphere to obtain a guest concentration of 1 m
A deuterated porphyne/sodium polystyrene sulfonate film of M was obtained.

This film has a wavelength of 645 nm and an intensity of 1 mW/cm ²
PHB holes were formed by irradiating with laser light. FIG. 2 illustrates the relationship between the temperature of the sample and the half-width of the generated holes. In this sample
I was able to form a hole even at 60K.

Example 4 5,10,15,20-tetra(4-N,N,N-trimethylaminophenyl)porphinetetra(p
-Toluene sulfonate) (manufactured by Dojindo Laboratories)
5.9mg and 5g of sodium polystyrene sulfonate
A film of deuterated porphine/sodium polystyrene sulfonate with a guest concentration of 1 mM was obtained by heating and dissolving the solution in 50 ml of heavy water and drying it under a dry nitrogen atmosphere.

This film has a wavelength of 645 nm and an intensity of 1 mW/cm ²
By irradiating the laser beam at 60K,
A PHB hole was formed.

Example 5 30 g of 4-carboxybenzaldehyde and 13.4 g of pyrrole were reacted in refluxed propionic acid,
6.9 g of 5,10,15,20-tetra(4-carboxyphenyl)porphine was obtained. This was reacted with an aqueous solution containing 4 equivalents of sodium hydroxide to obtain tetrasodium 5,10,15,20-tetra(4-carbonatophenyl)porphine.

Add 3.4 mg of this tetrasodium 5,10,15,20-tetra(4-carbonatophenyl)porphin and 5 g of sodium polystyrene sulfonate to 50 ml of heavy water.
A film of deuterated porphine/sodium polystyrene sulfonate with a guest concentration of 1 mM was obtained by heating and dissolving the mixture and drying it under a dry nitrogen atmosphere.

This film has a wavelength of 645 nm and an intensity of 1 mW/cm ²
By irradiating the laser beam at 60K,
A PHB hole was formed.

Example 6 Tetrasodium 5,10,15,20-tetra(4
-Sulfonatophenyl) porphine (manufactured by Wako Pure Chemical Industries, Ltd.) (40 mg) was dissolved in a mixed solution of 10 ml of tetramethoxysilane (manufactured by Shin-Etsu Chemical) of 20 ml of methanol in which active protons were deuterated, and 20 ml of heavy water, and then 0.1N Gelation was carried out using 0.5 ml of ammonia water as a catalyst. By drying this under a dry nitrogen atmosphere, a film of deuterated porphine/silicate glass was obtained.

This film has a wavelength of 645 nm and an intensity of 1 mW/cm ²
By irradiating the laser beam at 60K,
A PHB hole was formed.

[Effects of the Invention] The porphine-based PHB recording material of the present invention has a narrow half-width of holes generated at liquid helium temperature.
High recording multiplicity. In addition, holes can be formed even at temperatures of about 60K.

[Brief explanation of the drawing]

FIG. 1 illustrates the relationship between the sample temperature and the half-value width of the PHB hole in Example 2. Second
The figure illustrates the relationship between the sample temperature and the half-value width of the PHB hole for Example 3.

Claims (1)

[Scope of Claims] 1. A composition comprising a guest component and a host component as main components, wherein (a) the guest component is a porphyne derivative having an ionic group represented by the following general formula [A], (b) The host component is a polymer that does not have active protons that can be exchanged with deuterium in the guest component. Porphyne-based PHB recording material characterized by the following. (In the formula, D is deuterium, and at least one selected from X ₁ , X ₂ , X ₃ , _and It is a heterocyclic group, and the others are hydrogen atoms or nonionic groups.)